Device of open-wire multiple conductors



Dec. 10, 1957 A. K. DIETSCH DEVICE OF OPEN-WIRE MULTIPLE CONDUCTORSFiled Jan. 19', 1954 3 Sheets-Sheet 1 mmmw w v 02L? D lllllllll".

llti KI Dec. 10, 1957 A. K. DIETSCH 2,816,173

DEVICE OF OPEN-WIRE MULTIPLE CONDUCTORS Filed Jan. 19, 1954 5Sheets-Sheet 2 Fig. 4

DEVICE on ornN-wmn MULTIPLE CONDUCTORS Arne Kurt Dietsch, Enskede,Sweden, assignor to Telefonairtiebolaget L M Ericsson, Stockholm,Sweden, a corporation of Sweden Application January 19, 1954, Serial No.404,389

Claims priority, application Sweden March 4, 1953 2; Claims. (Cl.179-4754) The present invention refers to relay selectors for automatictelephone systems, for example multiple relays or cross-bar switches,and relates to a device for controlling the contact springs andfastening open-wire multiple conductors.

The object of the invention is to support the contact springs indetermined rest positions so, that deterrrnned contact intervals areobtained in relation to one or several open wire conductors and that anindividual adjustment of the contact springs is avoided, and cons sts inan oblong cast block of electrically non-conducting material with afirst lateral side facing the contact springs and a second lateral sidefacing the multiple conductors being provided with at least onelongitudinal row of funnel-shaped holes between said two lateral sides,the contact springs being introduced into said holes, and withlongitudinal furrows in said second lateral side, the multipleconductors being located in said furrows, which cut said holes.

The invention and the application thereof to cross-bar switches is shownin the accompanying drawings, Figs. l-S, and the application thereof toa multiple relay is shown in the accompanying drawings, Figs. 6-7.

Fig. 1 shows the upper portion of a cross-bar switch with an operatingbar unit P and five selecting bar units S mounted in a frame 1.

Figs. 2-3 show an embodiment of the selecting bar units.

Fig. 4 shows another embodiment of the selecting bar units.

Fig. 5 shows the bar support 2 for the operating bar unit.

As appears from Fig. 1, the cross-bar switch consists of a frame 1,which supports a number of vertical units S, here called selecting barunits, and a number of horizontal units P, here called operating barunits. A selecting bar unit is shown in Figs. 23. Only one operating barunit P is drawn in Fig. 1. Each operating bar unit consists of a barsupport 2;, which is more accurately shown in Fig. 5, two flanges 3 and4, an operating bar 6 with pertaining electromagnet 5. The electromagnet5 is mounted on the flange 3, which latter also supports a contactspring group 7. The operating bar 6 is turnably mounted in the flanges 3and 4, which are screwed within and kept together by the bar support 2.The operating bar is built in one piece with the armature of theoperating magnet 5 and actuates on one hand the contact spring 13 of themultiple in Fig. 2, and on the other hand the contact spring group 7.

The selecting bar unit according to Figs 23 is double, i. e. comprisestwo groups of vertical conductors 19 with pertaining contact springs 18,a selecting bar 14, and an electromagnet 17', and consists of an oblongmetal sheet 11 mounted on both sides and supporting on each side alongitudinal bar 12 of insulating material, on which a group ofconductors 19 are fastened, together with the contact springs for thecrossing points pertaining to the United States Patent 0 2,816,173Patented Dec. 10, 1957 group, between the conductors 19 and theoperating bar units of the cross-bar switch. A saving as well in costsas in space is evidently obtained by means of double mounting.

Fig. 3 shows the selecting bar unit seen from the left, whereby aportion is supposed to be cut off along the lines A-B--, B-C, and 0-D inFig. 2.

The bar 12 has a U-shaped cross section with two sidepieces and onecentral piece. The conductors 19 rest against and are fastened to thecentral piece. The contact springs 18 consist of wires with cylindricalsilver contacts 18a and are fastened on the side pieces at some distancefrom the conductors 19. Each contact spring 18 is soldered to one of theconductors 19 at the crossing point.

The contact springs at each crossing point are kept together by alifting bar 16 of insulating material, the aspect of which appears fromFig. 3. The lifting bar is provided with an extension 16a, on which anindicating means 15 of metal sheet or any other suitable material isturnably mounted. The indicating means 15 is provided with flaps, 15a,15b and 150. A spring 21 rests against the flap 15b and presses the flap15c against a jack in the selecting bar 14. The flap can be bent eitherupwards or downwards by means of a bending tool, and the flap 15a servesas contact against the operating bar 6, when the springs 18 are to belifted.

The selecting bar 14 is stretched between a spring 20 and a clasp 17which is fastened to the armature 17a of one of the selecting magnets17, for example 17b. The spring 20 furthermore actuates a contact springgroup The metal sheet 11 is provided with a support lla for determiningthe position of the contact springs in relation to the conductors in theoperating bar units P. The operating bar units can be moved verticallyand the supports 11a can be bent sideways. When the selecting bar unitis removed from the frame 11, the lifting bar 16 rests with itsextension 16a on the support 1111. The lower part of the metal sheet 11is bent on one side and supports a magnet system 17 consisting of a flatyoke with four legs, the middle ones being provided each with a coil 17aand 17b and constituting the cores of the two selecting magnets. Thearmatures of the selecting magnets rest against the outer legs of theyoke 17c and are kept in a position by means of a supporting sheet 17dof brass, which is screwed to the yoke 17c and constitutes on one hand asupport for the armatures 17s in unoperated position and on the otherhand a guiding bearing for the selecting bars 14.

The contacts 18:: of the contact springs 18 are introduced into holes inthe bar support 2. The contact springs are stretching on one handdownwards and on the other hand towards the metal sheet 11, so that thelifting bar rests against the support 11a, when the selecting bar unitis removed from the frame 1. When the selecting bar unit is introducedinto the frame, the contact springs rest in the hole 212 of the barsupport 2 in Fig. 5.

The bar support 2. consists of a strip of insulating material withlongitudinal furrows and transversal rows of holes 2b. The furrows cutthe holes 2%. Conductors 2a are located in the furrows. The conductorsare provided at each hole with an angular bending and are, on the rightside of the strip, bent perpendicularly and passed through holes 201 inthe strip. The protruding part 2e serves as soldering point forsoldering a conductor wire. There are grooves 2c on the edges of thestrip for determining the mutual position of the operating bar units andthe selecting bar units.

The angular bending of the conductors at each hole 2b is suitablyelfected after the conductors 2a have been laid in the furrows of thestrip. The purpose of the headings is to provide two contact points whenthe cylindrical contact 18a of a contact spring 18 is lifted against thetip of the angle.

The cross-bar switch functions in the following manner. The selectingmagnet 17b attracts its armature 17a, moving the selecting bar 14downwards. The indicating means 15 swings so that the flap 15a hitsagainst the operating bar 6 and is kept pressed against said operatingbar by means of the spring 21. The operating magnet 5 attracts itsarmature, thus causing the operating bar 6 to lift the indicating means15, which in its turn actuates the lifting bar 16 and the contactsprings 18. The contacts 18a are lifted towards the angular bendings atthe holes 2b and come into contact with the conductors 2a. When theselecting magnet releases its armature the selecting bar is restored tothe position shown in Fig. 2, but does not come into touch with the flapc of the indicating means 15, since said means is lifted by the bridge6. The selecting bar can thereafter be raised and lowered withoutaffecting the indicating device 15. When the operating bar 6 is releasedthe contact springs 18 are restored to the position shown in Fig. 2. Theflap 150 hits against the selecting bar 14 and the indicating means 15swings back to initial position.

The hole in the metal sheet 15 for the lifting bar 16 shown in Fig. 2 isshaped as a sector and leaves only a small play between the curve of thesector and the lower part of the lifting bar. Since the flap 15a hitsagainst the operating bar 6, there is no play between the operating barand the indicating means. The lifting bar 16 is furthermore cast roundthe contact springs 18, or else the contact springs 18 are inserted intotightly fitting holes in the lifting bar so that there can be no playthere either. The rest position of the selecting bar 14 is adjusted bymeans of a screw 23 fastened into the sheet 17d. The position of thesheet 15 is further adjusted by bending the flap 15c. By letting thecontacts 18a rest in the hole 2b in the bar support 2 and determiningthe mutual position of the bar support and the metal sheet 11 by meansof the support 11a, it becomes possible, on one hand to insert andremove the selecting bar units and the operating bar units easily, andon the other hand to obtain determined contact intervals and contactpressure.

The purpose of Fig. 4 is to prove that the selecting bar 14 can befastened outside the bar support 2 if it is turned by its electromagnetinstead of being raised and lowered. The indicating means then consistsof a flexible wire in full accordance with known cross-bar switches. Theoperating bar units can be inserted from the left according to Fig. 1and thereafter made to mesh with the selecting bar units S. Theselecting bar units S may in this case however not be removed until theoperating bar units P have been removed.

Figs. 6-7 show a multiple relay consisting of a frame 1, a bar support2, a number of contact spring groups 3 and an electromagnet 6 for eachcontact spring group. Fig. 6 shows the relay seen obliquely from behind,and Fig. 7 shows the relay seen straight from the front.

The bar support 2 consists of a cast strip of insulating materialprovided on the front with longitudinal furrows, in which open-wireconductors 9 are located. The strip is provided with a longitudinal rowof oblong holes 8, into which the contact springs 4 in the contactspring group 3 are inserted. The furrows cut all the holes 8. Theconductors 9 are bent 90 and introduced into holes 10 on one side of thestrip. The portions 11 of the conductors 9 which stuck out on the backof the strip serve for soldering the conductor wires.

Each of the contact spring groups 3 consists of a strip of insulatingmaterial in which contact springs 4 are cast.

The contact springs 4 are further kept together by a lifting bar 5 andprovided with cylindrical silver contacts, which are not drawn in thefigure. The lifting bar 5 rests against the armature 7 of the magnet 6.The magnets 6 are screwed to a frame mounting strip 12 along the under-side of the bar support 2. The contact spring groups are directlyactuated by the armature 7 of the magnets 6 and thereby brought intocontact with the conductors 9.

1 claim:

1. A contact arrangement for switches for automatic telephone systemscomposing a generally rectangular block of dielectric material havinglongitudinal grooves in one of its faces and a number of holes extendingperpendicular to said face and intersecting said grooves, said holesbeing arranged in rows perpendicular to said grooves, wire conductorsfitted within said grooves each having an angularly bent portion at eachpoint where a wire conductor intersects one of said holes, contactsprings resting in said holes normally spaced from said respective bentportion and lifting means selectively coacting to lift the contactsprings in one of said rows, each lifted contact spring making contactwith the corresponding wire conductor at two points within saidangularly bent portion.

2. A cross-bar switch for automatic telephone systems comprising a mainframe, a number of detachable multiple frames arranged on one side ofsaid main frame, a number of selectors arranged on the opposite side ofsaid main frame; each multiple frame comprising at least one set offixed multiple conductors, a selecting bar and a selecting magnet; eachselector comprising a set of fixed wire conductors crossing saidmultiple conductors and an operating bar with an operating magnet;switch contact springs in said cross-bar protruding from the multipleconductors at each crossing point between a set of said multipleconductors and the wire conductors of a selector; an indicating deviceand a lifting bar in the multiple frame at each of said crossing points;said indicating device being deflected by said selecting bar when saidselecting magnet is energized to engage said operating bar, saidoperating bar actuating said lifting bar when said operating bar isoperated by said operating magnet, actuation of the lifting baractuating said contact springs and said contact springs bringing eachconductor in a set of multiple conductors in contact with a wireconductor in the selector at the crossing point; each selectorcomprising a generally rectangular block of dielectric material havinglongitudinal grooves in one of its faces and a number of holes extendingperpendicular to said face and intersecting said grooves; said holesbeing arranged in rows perpendicular to said grooves; said wireconductors fitted within said grooves each having an angularly bentportion at each point where a wire conductor intersects one of saidholes; said contact springs resting in said holes normally spaced fromsaid respective bent portion, and each contact spring when lifted bysaid lifting bar making contact with the corresponding wire conductor attwo points within said angularly bent portion.

References Cited in the file of this patent UNITED STATES PATENTS2,434,373 Svensson et al. Jan. 13, 1948 2,577,067 Arthur Dec. 4, 19512,598,085 Vidgren et a1 May 27, 1952 2,680,783 Graybill et al. June 8,1954 2,718,559 Lunkvist et al. Sept. 20, 1955 2,731,516 Vincent Jan. 17,1956 2,758,158 Kruithof et al. Aug. 7, 1956

